A data processor for an analytical instrument (such as a chromatograph) should include a main processing unit connected to the analytical instrument, a keyboard for the input device and a display for the output device. With appropriate software, a general personal computer can be used as a data processor. But a specialized data processor is desirable for an analytical instrument because a specialized circuit can process data from the analytical instrument faster than a general circuit and specialized direct command keys make the operation more convenient.
Referring to a notebook type personal computer, a compact data processor is proposed as in FIGS. 7 and 8. The data processor is composed of a main body 21, a keyboard 22 provided on the top of the main body 21, and a lid 23 pivotally connected to the main body 21. On one face of the lid 23 is provided an LCD (liquid crystal display) panel. When the data processor is used, the lid 23 is raised upright as shown in FIG. 7 with the LCD panel facing the front. When the data processor is not used, the lid 23 is tilted down on the main body 21 as shown in FIG. 8, in which case the keyboard 22 cannot be operated and the LCD panel cannot be seen.
There is often a case where the keyboard of the data processor is used only at the beginning of an analysis (e.g. for setting up the conditions of the analysis) and no keyboard operation is necessary afterwards when data is being gathered and sent from the analytical instrument to the data processor. In such a case, if the lid 23 is tilted down, the operator cannot see the LCD panel and cannot recognize the progress of the analysis. If, on the other hand, the lid 23 is raised up, the data processor occupies a large space, and an unintentional touch of the keyboard may arise, which may cause an error in the analytical system. Another disadvantage of the structure is that the maximum rising angle of the lid 23 is not large enough in some cases so that the operator has to bend low to look into the LCD panel.
When the data processor is used for a chromatograph, it is desirable that the operator can perform, when necessary, a complicated data processing (such as an intensive and many-sided data analysis on the data collected through an analysis or a development of a new analytical method) using a full keyboard (including the a to z alphabetical keys). Once an analysis is begun, it is necessary to use only a minimum number of keys to operate the analysis (e.g., start/stop of the analysis or minor changes in the analytical conditions). The other keys are unnecessary and may even bring about an unintentional touch causing malfunctions of the analytical instrument.